The away side dominated the rest of the opening period though and, after setting up Kai Havertz's 20th-minute goal, Brandt calmly made it 3-1 10 minutes later.

Mainz almost pulled one back in the 42nd minute when Aaron Carico crashed a shot against the crossbar.

The hosts were immediately punished as Bellarabi, who had struck the woodwork at 2-1, added a fourth a minute later by collecting a pass from Brandt to find the bottom left corner.

And star man Brandt had the final say with 26 minutes remaining, dancing through the Mainz defence and coolly slotting into the bottom right corner past goalkeeper Florian Muller following a neat one-two with Kevin Volland.

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